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BACKGROUND: This study examined whether sick leave due to severe stress (stress leave) and duration of leave are associated with future cancer risk.

METHODS: We conducted a matched case-control study using complete-population data from Swedish national registers (2005 to 2018), including 516,678 primary cancer cases and 2,357,433 matched controls. Odds ratios (OR) were calculated by conditional logistic regression and adjusted for pre-specified confounders.

RESULTS: Stress leave of any duration, reported to the Swedish Social Insurance Register, was associated with a slightly increased cancer risk, with the highest risk estimate for 1-30 versus 0 days (adjusted OR 1.05, 95% CI 1.02-1.09). In men, a clear exposure-response trend was present. We observed increased risks of prostate cancer (adjusted OR for > 90 days: 1.10, 95% CI 1.01-1.20) and cervical cancer (adjusted OR for > 90 days: 1.11, 95% CI 1.05-1.17, including cancer in situ). In etiology-based analyses, a positive association was found for smoking-related cancers, and the risk relationship for non-cervical HPV-related cancers was similar to that for cervical cancer. Risk estimates were above one for several types of stress in relation to overall cancer risk, including an exposure-response trend for acute stress reactions (p-trend 4.0 × 10-4) but a null association for post-traumatic stress disorder.

CONCLUSIONS: Stress leave was associated with a modestly higher risk of cancer overall and prostate and cervical cancers specifically. Regardless of whether the link is biological or reflective of lifestyle mediators or for cervical cancer, lower participation in screening, these findings suggest a potential relevance of severe stress for cancer prevention.

Background: Stress is a commonly perceived cause of cancer, but the evidence to date is limited and inconclusive. We examined work-related stress in relation to cancer incidence in a population-based cohort, with outcome data from Swedish national registries.

Methods: The study population included 113,057 participants in the Västerbotten Intervention Programme. HRs were estimated using Cox proportional hazards regression, for cancer overall and for types with ≥500 cases, and adjusting for several potential confounders. The primary exposure was prediagnostic work-related stress, using the well established Karasek job demand/control model. Demand and control variables were dichotomized at the median, and participants were classified according to combinations of these categories. We also considered social network and aspects of quality of life.

Results: "High-strain" work (high demand/low control) was not associated with cancer risk compared with "low-strain" work (low demand/high control): multivariable HR 1.01 [95% confidence interval (CI), 0.94-1.08] for men and 0.99 (95% CI, 0.92-1.07) for women. Results were also null for most cancer types assessed: prostate, breast, colorectal, lung, and gastrointestinal (GI). The risk of GI cancer was lower for "passive" (low demand/low control) versus "low-strain" work, particularly for colorectal cancer in women: multivariable HR 0.71 (95% CI, 0.55-0.91), but statistical significance was lost after adjustment for multiple testing.

Conclusions: The findings of this population-based, cohort study do not support a role for work-related stress in determining cancer risk.

Impact: This study helps fill an important knowledge gap given the common concern about stress as a risk factor for cancer.

Objective: To investigate whether low molecular organic biomarkers could be identified in blood samples from vibration exposed workers using a metabolomics.

Methods: The study population consisted of 38 metalworkers. All participants underwent a standardized medical examination. Blood samples were collected before and after work shift and analyzed with GC-TOFMS. Multivariate modeling (orthogonal partial least-squares analysis with discriminant analysis [OPLS-DA]) were used to verify differences in metabolic profiles.

Results: Twenty-two study participants reported vascular symptoms judged as vibration-related. The metabolic profile from participants with vibration-induced white fingers (VWF) was distinctly separated from participants without VWF, both before and after vibration exposure.

Conclusion: Metabolites that differed between the groups were identified both before and after exposure. Some of these metabolites might be indicators of health effects from exposure to vibrations. This is the first time that a metabolomic approach has been used in workers exposed to vibrations.

Introduction: Ca2+ regulatory excitation-contraction coupling properties are key topics of interest in the development of work-related muscle myalgia and may constitute an underlying cause of muscle pain and loss of force generating capacity.

Method: A well-established rat model of high repetition high force (HRHF) work was used to investigate if such exposure leads to an increase in cytosolic Ca2+ concentration ([Ca2+]i) and changes in sarcoplasmic reticulum (SR) vesicle Ca2+ uptake and release rates.

Result: Six weeks exposure of rats to HRHF increased indicators of fatigue, pain behaviors, and [Ca2+]i, the latter implied by around 50–100% increases in pCam, as well as in the Ca2+ handling proteins RyR1 and Casq1 accompanied by an ∼10% increased SR Ca2+ uptake rate in extensor and flexor muscles compared to those of control rats. This demonstrated a work-related altered myocellular Ca2+ regulation, SR Ca2+ handling, and SR protein expression.

Discussion: These disturbances may mirror intracellular changes in early stages of human work-related myalgic muscle. Increased uptake of Ca2+ into the SR may reflect an early adaptation to avoid a sustained detrimental increase in [Ca2+]i similar to the previous findings of deteriorated Ca2+ regulation and impaired function in fatigued human muscle.

Exhaustion disorder (ED) is a stress-related disorder that often implies a great burden on the individual patient as well as on society. Previous studies have shown that ED is associated with metabolic deviations, such as lowered fasting glucose. Several mechanisms have been discussed as a plausible explanation of the lack of energy described by these patients. Metabolic processes and reduced ability to mobilize energy have been suggested as important factors. This study investigated metabolomics in 20 patients diagnosed with ED and compared them with 21 healthy controls. Plasma metabolic profiles were examined in both fasting and nonfasting (postprandial) conditions. Blood plasma samples were analyzed for metabolite content using gas chromatography mass spectrometry. A total of 62 different metabolites were simultaneously detected in each of the samples. Multivariate models indicated systematic differences between patients with ED and healthy controls in both their fasting and nonfasting plasma metabolite levels. Lysine and octadecenoic acid were more abundant and glutamine, glycine, serine and gluconic acid were less abundant in the patients across both conditions. In the present study, we comprehensively and simultaneously screen for changes in a large number of metabolites. Our results show a difference in systemic metabolites between patients with exhaustion disorder and healthy controls both in the fasting and in the postprandial states. Here, we present new potential biomarkers mirroring exhaustion disorder metabolism.

Several studies have documented the importance of optimal work situation and the general well-being of early-career researchers (ECRs) for enhancing the academic performance of universities. Yet, most studies focused on specific categories of ECRs, or on specific academic disciplines as well as on specific outcomes. With this study, we recognize the need for a broader sample encompassing different categories of ECRs across academic disciplines. In a national survey of Swedish universities, the National Junior Faculty of Sweden (NJF) collected data from ECRs in order to study the influence of work situation and well-being on perceived scientific environment. We observed that work situation and well-being are interdependent and jointly influence each other in shaping the conditions for ideal scientific environment. Importantly, we employ structural equation model (SEM) analysis to account for the endogenous relationship between work situation and personal well-being in predicting perceived scientific environment. Results from SEM indicate that support from the university, work time management, job clarity, contract length and quality of life satisfaction were related to the perceived possibility of conducting the best science. Our research also highlighted individual differences across demographic factors and contract length in the perceived work situation and the possibility of conducting the best science.

Socioeconomic factors affect choice of diet, that is, dietary fiber intake. Underreporting of food consumption in diet surveys has been reported higher in low-income, low-education groups compared to high-income, high-education groups. This paper examines in a socioeconomic homogenous low-income low-education group of females the relation between dietary fiber intake and overweight and scrutinizes if the level of underreporting is equally large in normal-weight and overweight groups. Thirty-four female health care workers classified as either normal-weight () or obese () based on BMI, fat percentage, and waist circumference participated. A detailed food-diary was used to record their dietary intake in 9 days. Average dietary fiber intake in the normal-weight group was 2.73 +/− 0.65 g/MJ, while it was 2.15 +/− 0.64 g/MJ for the women in the obese group. In both groups, the overall food intake was underreported. In spite of a significantly lower dietary fiber intake in the obese group, the present population of women working within health care all showed an overall low dietary fiber intake and a general underreporting of food intake. These results indicate a clear need for dietary advice especially on fiber intake to increase general health and decrease weight.

Background: Systemic inflammation is known to induce sickness behaviors, including decreased social interaction and pain. We have reported increased serum inflammatory cytokines in a rat model of repetitive strain injury (rats perform an upper extremity reaching task for prolonged periods). Here, we sought to determine if sickness behaviors are induced in this model and the effectiveness of conservative treatments.

Methods: Experimental rats underwent initial training to learn a high force reaching task (10 min/day, 5 days/week for 6 weeks), with or without ibuprofen treatment (TRHF vs. TRHF + IBU rats). Subsets of trained animals went on to perform a high repetition high force (HRHF) task for 6 or 12 weeks (2 h/day, 3 days/week) without treatment, or received two secondary interventions: ibuprofen (HRHF + IBU) or a move to a lower demand low repetition low force task (HRHF-to-LRLF), beginning in task week 5. Mixed-effects models with repeated measures assays were used to assay duration of social interaction, aggression, forepaw withdrawal thresholds and reach performance abilities. One-way and two-way ANOVAs were used to assay tissue responses. Corrections for multiple comparisons were made.

Results: TRHF + IBU rats did not develop behavioral declines or systemic increases in IL-1beta and IL-6, observed in untreated TRHF rats. Untreated HRHF rats showed social interaction declines, difficulties performing the operant task and forepaw mechanical allodynia. Untreated HRHF rats also had increased serum levels of several inflammatory cytokines and chemokines, neuroinflammatory responses (e.g., increased TNFalpha) in the brain, median nerve and spinal cord, and Substance P and neurokinin 1 immunoexpression in the spinal cord. HRHF + IBU and HRHF-to-LRLF rats showed improved social interaction and reduced inflammatory serum, nerve and brain changes. However, neither secondary treatment rescued HRHF-task induced forepaw allodynia, or completely attenuated task performance declines or spinal cord responses.

Conclusions: These results suggest that inflammatory mechanisms induced by prolonged performance of high physical demand tasks mediate the development of social interaction declines and aggression. However, persistent spinal cord sensitization was associated with persistent behavioral indices of discomfort, despite use of conservative secondary interventions indicating the need for prevention or more effective interventions.

BACKGROUND:

Several RCT studies have aimed to reduce either musculoskeletal disorders, sickness presenteeism, sickness absenteeism or a combination of these among females with high physical work demands. These studies have provided evidence that workplace health promotion (WHP) interventions are effective, but long-term effects are still uncertain. These studies either lack to succeed in maintaining intervention effects or lack to document if effects are maintained past a one-year period. This paper describes the background, design and conceptual model of the FRIDOM (FRamed Intervention to Decrease Occupational Muscle pain) WHP program among health care workers. A job group characterized by having high physical work demands, musculoskeletal disorders, high sickness presenteeism - and absenteeism.

METHODS:

FRIDOM aimed to reduce neck and shoulder pain. Secondary aims were to decrease sickness presenteeism, sickness absenteeism and lifestyle-diseases such as other musculoskeletal disorders as well as metabolic-, and cardiovascular disorders - and to maintain participation to regular physical exercise training, after a one year intervention period. The entire concept was tailored to a population of female health care workers. This was done through a multi-component intervention including 1) intelligent physical exercise training (IPET), dietary advice and weight loss (DAW) and cognitive behavioural training (CBT).

DISCUSSION:

The FRIDOM program has the potential to provide evidence-based knowledge of the pain reducing effect of a multi component WHP among a female group of employees with a high prevalence of musculoskeletal disorders and in a long term perspective evaluate the effects on sickness presenteeism and absenteeism as well as risk of life-style diseases.

TRIAL REGISTRATION:

NCT02843269 , 06.27.2016 - retrospectively registered.